The invention refers to a separating conveyor for the transfer of unit loads, in particular of pieces of airplane luggage, as per the preamble of Claim 1. From the (printed) German Pat. specifications DE 42 25 491 C1, an installation/ device for emptying containers is known, which is arranged along the conveyor""s path. The containers serve primarily to transport individual pieces of airplane luggage. The installation for emptying the containers consists essentially of several fixed, spaced out and consecutively mounted tilting arms, pivotably mounted in the transport direction; their centers rest on an axis extending in the transport direction and allowing the arms to be swiveled to both sides. Furthermore, the area of the installation for emptying the containers is provided with disc-shaped carrier rollers of the roller conveyor type, whichxe2x80x94seen in the transport directionxe2x80x94are arranged consecutively and in single file. The design/ execution of the carrier rollers and the lower surface of the containers provided with a central, continuous slot in the transport direction are chosen in such a way that carrier-roller-supported containers can be tilted on the carrier rollersxe2x80x94to either sidexe2x80x94to up to approx. 45xc2x0. The tilting movement that serves to let the transported container contents slide down to the branching (off) conveyor that runs adjacent to the emptying installation is carried out by the two-armed tilting arms. For this purpose, the tilting arms are provided, at their opposite ends, with guides in the form of guide rollers that are pivotable around horizontal axles, which engage- in correspondingly arranged guide bars-webs on the container in order to transfer the tilting arms"" swivel movement to the containers. The distance between the tilting arms, successively arranged in the transport direction, is less than the length of the containers, so that the containers can be transferred during the tilting action to the following transport-direction-oriented tilting arm, which is in the same tilting position.
This emptying/unloading installation is suitable for a large number of applications, its outstanding characteristic being the fixed placement of the tilting arms. However, the transfer (flow) rate is limited by the fact that there has to be a sufficiently large gap between each of the containers to be emptied, so that the tilting arms have sufficient time to return from the swung-out position to the horizontal position for accepting the next container.
Furthermore, also already known from the German patent specifications DE 21 51 439 C2, is a tilting installation for unit loads that is arranged along the path of the conveyor, and consists, essentially, of dish-shaped carrier units, movable in the transport direction, whichxe2x80x94in order to off-load the unit loadsxe2x80x94are pivotable, either to the right or the left side, around an axis proceeding in the transport direction. As a result, the unit loads can be transferred, specifically, to an adjacent separation conveyor. Each of the dish-shaped carrier units is mounted, via a tilting arm, on individual traveling undercarriages, which are linked consecutively to each other in the transport direction. Thus, the traveling undercarriages form an endless revolving chain, that is guided around a reversing guiding wheel at the junction points with the adjacent conveyor belt. For the tilting action, the load units are transferred from the adjacent conveyor belt to the chain""s upper stringer, and will either be tipped out in the direction of the branching off conveyor belt, or will be transferred, for further transport, to the conveyor belt that adjoins the tilting installation. The dish-shaped carrier unit""s tilting movement is effected by a lever arm that engages the tilting arm. Essentially, this lever arm extends perpendicularly downwards, and at its end, facing away from the tilting arm, it is provided with a guide roller. The guide roller is carried in a track that runs alongside the stadium-shaped, circular-running traveling path of the carriers units. This locks the dish-shaped carrier unit into its horizontal position. For tilting purposes, switchable switches are provided along the guide, which permit reroutingxe2x80x94according to the desired tilting direction, either to the right or left of the guide rollerxe2x80x94to a tilting rail that is arranged either above or below the guiding rail. By rerouting the guide roller, the lever arm is drawn, accordingly either downwards, or it is pushed upwards, whereby the dish-shaped carrier unit is swiveled to the right or left. The shifting of the switching elements is effected via a double-acting pneumatic cylinder, whose horizontally oriented movement is convertedxe2x80x94via two interacting rollers, each provided with a guide bar bracketxe2x80x94into swiveling the switches in a vertical direction.
It is the task of the present invention to create a separation conveyor for unit loads, specifically for pieces of airplane luggage, that is provided with an optimized drive for moving the switch rails, in order to initiate the tilting movement of the tilting arms. This goal is achieved, as per the characteristics stated in Claim 1, with a tilting installation for unloading unit loads from containers. Advantageous further developments of the invention are indicated in the sub-claims 2 through 10.
In order to execute the containers"" tilting movement, each tilting arm is provided with a lever arm that is pivotably joined outside its axis. Essentially, the lever arm is vertically aligned and is provided with a guide roller at its end facing away from the tilting arm. In order to hold the tilting arm in its horizontal transport position, the guide roller engages a guide rail that runs parallel to the stadium-shaped track. In order to be able to swing out the tilting arms, switchable rails have been provided along the guide rails, which are pivotable around a switching joint, whose axis is aligned horizontally and at right angles to the transport direction, and via which the guide rollers can be rerouted from the guiding rail to a tilting rail that is vertically off set in relation to the guiding rail. Due to the resulting traction or, respectively, the pressure force that is exerted on the lever arm in the vertical direction, the tilting arm and, consequently, the container attached to it, is swung out either to one or the other side of the tilting device. This development of the tilting mechanism has turned out to be very simple as to its structure/design, since, essentially, it is based on mechanical component parts. Furthermore, this type of mechanical solution is, relatively, much less trouble prone.
A switch railxe2x80x94with its pivotably mounted switch element and arranged along the guide rail,xe2x80x94has been found to be advantageous. The length of this switch rail is approximately the same length as that of a container. This results in a relatively gentle tilting movement of the tilting arms and, thus, of the tilting container. The switch rail can be swung from its resting position to its operative position by means of a drive (actuator). In its operational position, the switch rail connects the guide rail with a tilting rail that is assigned to it.
As a drive for the swivel movement of the switch rail, the use of a flat cam gear with rectilinear and swivel joints of the Geneva-type stop has been found advantageous, since this guarantees that, both in the resting and the operational position of the tilting rail, the drive, which preferably consists of a series-connected electric motor, is not under torsional strain, and that the switch rail""s supporting forces are fed directly into the gear""s driving shaft, making the cam gear self-locking.
This cam gear is executed as a rotatable plate with a fixed stud, arranged on a driven shaft, that consists essentially of a studxe2x80x94arranged off-set in relation to the driven shaft that engages the slot of a slotted disc that rotates coaxially to the rotatable stud plate. The slotted disc""s end opposite the slot has a pivotably joined connecting tie rod that is connected to the switch rail, and which serves to convert the slotted disc""s rotary movement into a lifting or lowering movement of the switch rail. In order to make possible the previously described self-locking of the cam gear, the rotatable stud plate, as well as the slotted disc have been provided with arch-shaped (curved) contact surfaces, which adjoin both in the resting and the operational position of the rotatable stud plate and the slotted disc and, thereby, relieve the stud. While between the two positions, the rotatable stud plate can be swiveled by 90xc2x0, and in both swivel positions of the slotted disc, the slot""s longitudinal section is arranged tangentially to the stud""s shaft and at a distance from it.
Furthermore, it is also advantageous to provide a double set of guide rails and tilting rails, whichxe2x80x94seen in the transport directionxe2x80x94are located at the right and left side below the tracks. This allows a switching element to be provided on the left side at the beginning of the tilting device""s track rails and to be followed shortly by a further switching element on the right side. The distance between switching elements corresponds to the spacing of the consecutively arranged tilting arms that jointly carry a container, which makes a simultaneous swing-out movement possible. Due to the staggered arrangement on the sides of the switching elements, it is possible to increase the speed of the traveling undercarriages, since the distance between the individual guide rollers is twice as long on one side of the tilting rails and, thus, there remains enough timexe2x80x94even at higher transporting speedsxe2x80x94to switch the switch rails into the desired position before the arrival of the next guide roller. For this purpose, the tilting arms that are arranged on the undercarriages are turned around by 180xc2x0, andxe2x80x94seen in the transport directionxe2x80x94guide rollers are provided which alternately engage the right-side or left-side rails.
The execution that allows the tilting arms to move along in the transport direction is achieved in that at least two tilting arms are assigned to a container during the entire tilting process and, thus, the tilting arm""s return movement into the horizontal position occurs together with the container; this makes it unnecessary to allow for additional time for the return of the tilting arms, thus optimizing the flow/transfer rate or, respectively, the length of the tilting device. Transfer rates of 2500 containers per hour can be achieved with a tilting device of the described type.
An especially advantageous means of attaching the containers on the tilting arms is to arrange permanent magnets at the ends of the tilting arms, as well as a material that the magnetic force will hold, in particular steel sheet metal that is placed on the outer bottom surface, if the container is made of plastic. The connection between the permanent magnets and the container is easily undone at the end of the tilting movement by the tilting arms"" downward tipping (dumping) out movement, and the container can safely be passed on to the subsequent conveyor belt. Due to the tilting movementxe2x80x94at the beginning and the end of the tilting device, seen in the transport directionxe2x80x94of the permanent magnets around an axis (oriented at right angles to the transport direction) that places them either into or out of their essentially horizontal position at the tilting arms, a gentle coupling and/or uncoupling process of the container is achieved. Furthermore, the disc-shaped design of the holding meansxe2x80x94where one disc surface faces towards the container to be attachedxe2x80x94and the slightly angled movable positioning of the holding means on the tilting arms, result in the contact of the holding means being as holohedral as possible at the containers"" lower surface, and, consequently, the containers are held securely on the tilting arms and are held also during the tilting movement.
It has also proven to be an advantage that the undercarriages are provided with rollers, which roll on a stadium-shaped trackxe2x80x94seen in the transport directionxe2x80x94, that the traction medium, together with the undercarriages arranged on it, is guided over/via two reversing guide wheels, which are positioned in the area at the ends of the track rails.
Below follows a detailed explanation of the invention, based on the attached drawings. Shown are in
The invention refers to a tilting device for emptying containers carrying unit loads (in particular pieces of airplane luggage), which is arranged along the course of a conveyor belt; the tilting device has at least one adjoining branch-off conveyor; with tilting arms arranged consecutively and in the transport direction, whichxe2x80x94in order to empty the containersxe2x80x94can all be swiveled sideways around an axis that extends mostly horizontally in the transport direction; the tilting device is also provided with at least two tilting arms for passing the containers on between the conveyor belts; at least two of the tilting arms are detachably connected to a container by holding means.
In order to create a container-emptying tilting device that has an optimized flow/transfer rate, it is proposed that for the tilting movement of the containers (2), each tilting arm (8) flexibly (articulated) engagexe2x80x94outside of its axis (19)xe2x80x94a coupling rod (12), that essentially is vertically aligned, and on whose end facing away from the tilting arm (8), a guide roller (14) is mounted, whichxe2x80x94in order to hold the tilting arms (8) in their horizontal transport positionxe2x80x94is carried/guided in a guiding rail (15) that proceeds parallel to a track rail (6); in order to swivel the tilting arms (8) around an axis (9), the guide roller (14) can be rerouted via a switchable switching element (17) to a tilting rail (16), arranged off-set to the guiding rail (15); the switching elements (17) consist of a switching rail (14) that, in its horizontal resting position, is arranged along the extent of the guiding rail (15); it can be swung, by means of a drive (32) into a swung-out operational position that connects the guiding rail (15) with the assigned tilting rail (16); the switching rail (41) can be swiveled via a cam gear of the Maltese Cross type. (See Illustration 4).
The invention refers to a separating conveyor for the transfer of unit loads, in particular pieces of airplane luggage, from a conveyor belt (3), to at least one adjoining branching-off conveyor withxe2x80x94in the transport direction (F) consecutively arrangedxe2x80x94traveling undercarriages (7), movable along a track rail (6), whichxe2x80x94via a driven traction medium (4)xe2x80x94are interconnected to form an endless, revolving chain; the traveling undercarriages (7) are provided with tilting arms (8), each of which, in order to transfer to load units, can be swung sideways around a mostly horizontally (in the transport direction F) extending axis (9); for the tilting movement of the tilting arms (8) around the axis (9) via a switchable switching element (17), the guiding roller (14) can be rerouted to a tilting rail (16), that is off-set and vertically aligned to the guiding rail (15). The switching rail (41) can be swiveled by a cam gear of the Maltese Cross type, which is providedxe2x80x94aligned in the transport directionxe2x80x94with an impellable (drivable) pin disc (34), which by means of a pin (35) engages a slot (36) arranged on a slotted disc (37) which bears a tie rod (40), that converts the turning movement of the slotted disc (37) into a lifting or lowering movement of the switching rail (41). (See FIG. 4).